Design, simulation and validation of a viscoelastic damper for structural vibration reduction

Resumo

Passive dampers are used to reduce structural vibration levels in a wide range of applications. Rubber
is still one of the most widely used materials. However, to simulate the viscous-elastic properties, complex
dynamic models are frequently required. In this project, we designed, synchronized, and built a viscous-elastic
damper for use on a steel frame structure. FRF was used to identify the structure's initial modes, and vibration
levels were measured using a shake table and an impact hammer. To describe and simulate the entire system, Finite
Element Models were developed. To linearize the viscous-elastic damper behavior we built a sample and tested it
to estimate equivalent proprieties values. Based on those equivalent properties, the mass and shape of a new sample
were adjusted to synchronize the frequency and optimize the damper effect. The resulting geometry was fabricated
and applied at the structure. The structure was excited over again and the vibration levels were compared to
previous results. The results show a 48.7 percent reduction in vibration levels with only a 8.3 percent increase in
mass (damper mass). The experimental tests and simulation comparison also demonstrates good agreement.